Give first the step you will use to separate the variable and then solve the equations: (a) x-1 = 0 (b) x+1 = 0

(a) x-1 = 0
⇒ x-1+1 = 0+1 [Adding 1 both sides]
⇒ x = 1
(b) x+1 = 0
⇒ x+1-1 = 0-1 [Subtracting 1 both sides]
⇒ x =-1

Class 7 Maths Chapter 4 Exercise 4.2

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